Search

Maize is susceptible to colonization by Aspergillus flavus,which is the major aflatoxins producing fungus. Aflatoxins are fungal secondary metabolites that have been reported to adversely affect normal cell metabolism and seed germination. In this study, 106 maize seed samples were sampled across 13 states throughout India, and were screened for incidences of fungal infection. Among the seed samples collected across India nearly all maize seed samples were found to be infected with Aspergillus. All morphologically confirmed isolates belonging to Aspergillussection Flaviwere subjected to various aflatoxin, biochemical, physiological and genotype assays, as well as phylogenetic analyses. Among 60 isolates tested, eight were non-aflatoxigenic in nature as determined by icELISA, and seven of those eight isolates showed absence of one or more aflatoxin cluster genes in PCR assay. The morphological, physiological and biochemical characterizations failed to show variation based on their toxigenicity. The phenetic and molecular genetic diversity could be observed based on RAPD and ISSR analyses and little isolate diversity could be determined based on geography or aflatoxigenicity. An inferred ITS sequence phylogeny segregated isolates into only two lineage groups: a large group I (including Ia and Ib) and small group II contained A. flavusisolates closely related to A. parasiticus.The current study highlights inherent diverse A. flavusinfections, exhibiting a range of aflatoxin concentrations, that are present in maize seeds and they are important because of the potential threat to agricultural production and consumption.

A total of 106 maize seed samples were collected from different agro-climatic regions of India. Sixty-two Fusarium isolates were recovered, 90% of which were identified as Fusarium verticillioides based on morphological and molecular characters. Use of the tef-1 gene corrected/refined the morphological species identifications of 11 isolates, and confirmed those of the remaining isolates. Genetic diversity among the Fusarium isolates involved multilocus fingerprinting profiles by Inter Simple Sequence Repeats (ISSR) UPGMA and tef-1 gene phenetic analyses; for which, we observed no significant differences among the isolates based on geographic origin or fumonisin production; most of the subdivision related to species. Genotyping was performed on the F. verticillioides isolates, using 12 primer sets from the fumonisin pathway, to elucidate the molecular basis of fumonisin production or non-production. One fumonisin-negative isolate, UOMMF-16, was unable to amplify nine of the 12 fumonisin cluster genes tested. We also used the CD-ELISA method to confirm fumonisin production for our 62 Fusarium isolates. Only 15 isolates were found to be fumonisin-negative. Interestingly, genotypic characterization revealed six isolates with various gene deletion patterns that also tested positive for the production of fumonisins via CD-ELISA. Our findings confirm the importance of molecular studies for species delimitation, and for observing genetic and phenotypic diversity, among the Fusaria.

Nuclear Overhauser effect spectroscopy (NOESY) gave full assignments of the 1H‐NMR spectra of the picrotoxane neurotoxins tutin, hyenanchin, picrotoxinin and picrotin, as well as the solution conformations of these compounds, consistent with molecular modelling. Fully assigned 13C‐NMR data are reported. Copyright © 2001 John Wiley & Sons, Ltd.

Nuclear Overhauser effect spectroscopy (NOESY) gave full assignments of the ¹H-NMR spectra of the picrotoxane neurotoxins tutin, hyenanchin, picrotoxinin and picrotin, as well as the solution conformations of these compounds, consistent with molecular modelling. Fully assigned ¹³C-NMR data are reported. Copyright © 2001 John Wiley & Sons, Ltd.

Natural antisense transcripts (NATs) have been detected in many organisms and shown to regulate gene expression. Similarly, NATs have also been observed in malaria parasites with most studies focused on Plasmodium falciparum. There were no reports on the presence of NATs in Plasmodium vivax, which has also been shown to cause severe malaria like P. falciparum, until a recent study published by us. To identify in vivoprevalence of antisense transcripts in P. vivaxclinical isolates, we performed whole genome expression profiling using a custom designed strand-specific microarray that contains probes for both sense and antisense strands. Here we describe the experimental methods and analysis of the microarray data available in Gene Expression Omnibus (GEO) under GSE45165. Our data provides a resource for exploring the presence of antisense transcripts in P. vivaxisolated from patients showing varying clinical symptoms. Related information about the description and interpretation of the data can be found in a recent publication by Boopathi and colleagues in Infection, Genetics and Evolution 2013.